JPH0312808A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To avoid short-circuit between conductive thin film coils and magnetic layers so as to improve the characteristic of a thin film magnetic head by forming a first conductive thin film coil in a first insulating layer and a second conductive thin film coil in a second insulating layer. CONSTITUTION:The first insulating layer 5 and a gap layer are formed on the ferromagnetic substrate with high magnetic permeability 1 by a prasma CVD method. The first conductive thin film coil 3 is formed on the first insulating layer 5 by a vapor deposition method and the like and then, the second insulating layer 6 with the second conductive thin film 7 is formed on it by the prasma CVD method and the like. Then, a third insulating layer 8 with the magnetic layer 2 is formed on the second conductive thin film coil 7 by the prasma CVD method and the like. Consequently, short-circuit between the conductive thin film coils 3 and that between the conductive thin film coils 3 and the magnetic layers, which occur through a part where the step coverage of the insulating layer is deteriorated can be prevented. Thus, short-circuit can be prevented, a characteristic can be improved and yield can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a thin film magnetic head, and is particularly used in a high-density magnetic recording/reproducing device.

<Conventional technology> Thin-film magnetic heads are often used to accommodate multi-track recording as recording density increases.1 The above-mentioned thin-film magnetic heads are manufactured by making full use of thin-film formation technology, photolithography technology, and etching technology. 1 in Figure 2.
A plan view of a thin film magnetic head for tracks viewed from above is shown. As shown in Figure 2, a high permeability ferromagnetic substrate l
In the gap formed by the magnetic layer 2 and the magnetic layer 2, several stages of conductive thin film coils 3.7 each having several turns are formed.

An example of the structure of a conventional thin film magnetic head will be explained using the manufacturing process diagram of FIG. FIG. 3 is a sectional view taken along line xx' in FIG. 2.

In FIG. 3(a), a first insulating layer 5 and a gap layer 9 with a first conductive thin film coil 3 are formed on a high permeability ferromagnetic substrate 1 by plasma CVD or the like.

In FIG. 3(b), a first conductive thin film coil 3 consisting of several turns is formed on the first insulating layer 5 by vapor deposition or the like, and then micro-etched by ion milling or the like to form a pattern. ing. In FIG. 3(c), a second insulating layer 6 with a second conductive thin film coil 7 is formed on the first conductive thin film coil 3 by a plasma CVD method or the like. In FIG. 3(d), a second conductive thin film coil 7 consisting of several turns is formed on the second insulating layer 6 by a vapor deposition method or the like, and then a pattern is formed by microfabrication etching by an ion milling method or the like. Reference numeral 4 denotes a through hole that connects the first conductive thin film coil 3 and the second conductive thin film coil 7.

In FIG. 3(e), a third insulating layer 8 together with the magnetic layer 2 is formed on the second conductive thin film coil 7 by a plasma CVD method or the like.

In FIG. 3(f), the magnetic layer 2 is formed on the third insulating layer 8 by sputtering or the like, and then patterned by micro-etching by RIE or the like.

<Problems to be Solved by the Invention> However, in the structure of the thin film magnetic head as described above, the first conductive thin film coil 3 and the second conductive thin film coil 7
As a result of the formation, the second insulating layer 6 and the third insulating layer 8 are partially thin due to the surface step difference to be transferred, and after microfabrication and etching, there is a gap between the first conductive thin film coil 3 and the second conductive thin film coil 7. Also, a short circuit occurs between the second conductive thin film coil 7 and the magnetic layer 2, which poses a problem that affects the characteristics of the thin film magnetic head.

In view of the above points, the present invention provides a structure that improves the characteristics and yield of a thin film magnetic head.

<Means for Solving the Problem> In order to achieve this object, in the thin film magnetic head of the present invention, the first insulating layer is etched into the shape of the first conductive thin film coil pattern, and then the first conductive thin film is etched. A first conductive thin film coil is embedded in the first insulating layer by microfabrication and etching.

Similarly to the above, for the second conductive thin film coil, the second insulating layer is etched in the shape of the second conductive thin film coil pattern, a second conductive thin film is formed, and the second insulating layer is formed by microfabrication etching. embedded in the layer.

Effects> This structure can prevent short circuits between the conductive thin film coils and between the conductive thin film coil and the magnetic layer, which would otherwise occur through the portions of the insulating layer with poor stamp coverage. Therefore, by embedding the conductive thin film coil in the underlying insulating layer, it is possible to prevent short circuits, improve characteristics, and improve yield.

<Example> An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a sectional view taken along the line x-x' in FIG. 2.

In FIG. 1(a), a first insulating layer 5 and a gap layer 9 with a first conductive thin film coil 3 are formed on a high permeability ferromagnetic substrate 1 by plasma CVD or the like.

The difference between FIG. 1(a) and FIG. 3(a) is that the groove 10 for embedding the first conductive thin film coil 3 is formed using photolithography technology and microfabrication etching technology such as RIE method, as shown in the figure. This is because the structure has been designed to be more structured.

In FIG. 1(b), a first conductive thin film coil 3 consisting of several turns is formed on the first insulating layer 5 by vapor deposition or the like, and then microfabricated and etched by ion milling or the like to form a pattern. In FIG. 1(c), a second insulating layer 6 with a second conductive thin film coil 7 is formed on the first conductive thin film coil 3 by a plasma CVD method or the like.

In FIG. 1(d), after the second insulating layer 6 is processed in the same manner as the first insulating layer 5, a second conductor thin film coil 7 is patterned. In FIG. 1(e), the second conductive thin film coil 7
A third insulating layer 8 together with the magnetic layer 2 is formed thereon by a plasma CVD method or the like.

In FIG. 1(f), a magnetic layer 2 is formed on the third insulating layer s by a spanking method or the like, and then a pattern is formed by micro-etching by a RIE method or the like.

The difference between FIG. 1(f) and FIG. 3(f) is that the step coverage deterioration of the insulating layers 5 and 6.8 is prevented by embedding the 3°7 portion of the coil in the underlying insulating layer 5.6. The structure is such that it is possible to avoid the short circuit between the coil 3 and the coil 7 and the short circuit between the coil 7 and the magnetic layer 2 that would otherwise occur.

<Effects of the Invention> As described above, in the thin film magnetic head of the present invention, the first conductive thin film coil is formed in the first insulating layer, the second conductive thin film coil is formed in the second insulating layer, It is possible to avoid short-circuits between conductive thin-film coils and short-circuits between conductive thin-film coils and magnetic layers, which are caused by step coverage deterioration due to surface steps that occur in conventional manufacturing methods, and improve the characteristics and yield of thin-film magnetic heads.

[Brief explanation of the drawing]

FIGS. 1(a) to (f) are cross-sectional views showing one embodiment of the present invention, FIG. 2 is a plan view of one track, and FIGS. 3(a) to (f) are cross-sectional views showing a conventional example. It is. DESCRIPTION OF SYMBOLS 1... High permeability ferromagnetic substrate, 3... First conductor thin film coil, 5... First insulating layer, 6... Second insulating layer, 7... Second conductor thin film coil.

Claims (1)

[Claims] (1) First and second conductive thin film coils consisting of several turns formed on the first and second insulating layers on the high magnetic permeability ferromagnetic substrate are embedded in the insulating layer underlying each coil. A thin film magnetic head characterized by: